Conventional sealing materials include sealing materials comprising foamed bodies, sealing materials comprising nonwoven fabrics, sealing materials comprising implanted fiber bodies, sealing materials comprising woven pile fabrics or other such woven fabrics, sealing materials comprising knit fabrics, sealing materials comprising rubber materials, and so forth. For example, such sealing materials are often used as end seal materials in powder carriers where surfaces of powder carriers constituting rotating bodies are partially exposed.
With respect to such sealing materials, a sealing material comprising woven pile fabric formed as a result of the overlapping of weft yarn and warp yarn constituting ground yarn has, for example, been proposed as an end seal material for a powder carrier which is a rotating body that comprises woven pile fabric which prevents leakage of toner, i.e., powder, in an electrophotographic image forming apparatus (e.g., see Patent Reference No. 1).
Moreover, a powder sealing material has been proposed which comprises knit pile fabric that is knit fabric having pile in which stretchability and loss of fibers from the knit fabric are controlled, and in which flow of toner, i.e., powder is furthermore controlled, and in which leakage of powder to the exterior is prevented (e.g., see Patent Reference No. 2).
Moreover, a sealing member has been proposed which comprises stripes in a pattern of bands having no pile which is a structure that makes efficient use of resources, permitting attainment of high performance as a seal while being a member that uses little yarn, and which is constituted from few operations, without need for fiber grooming operations to cause inclination of pile or shearing operations to achieve uniform pile height, and in which there is no production of raggedness during use, and which is therefore capable of being used in stable fashion, there being no cause for concern with respect to loss of fibers, and which moreover has excellent wear resistance, and which is an extremely high-quality sealing member, there being cause for concern with respect to detachment (e.g., see Patent Reference No. 3).
However, in recent years, as a result of the fact that problems with seal characteristics have become more prominent due to the fact that there have been advances in achieving decreased particle diameter in powder constituting toner due to the trend toward improved energy conservation, and there have been advances in achieving increased speed in devices, there has been increased focus on the problem of achieving good seal characteristics with respect to such powders, and on the problem of the heat due by friction at, e.g., the rotating body, i.e., roller, or powder carrier which contacts the sealing material, and so forth.
In particular, with respect to sealing materials for toners in electrophotographic image forming apparatuses, due to the trend in recent years toward improved image quality and to reduce the amount of toner consumed, in accompaniment to increase in speed of the device in addition to the decrease in toner particle diameter, there have been advances in achieving reduction in the melting point of the toner, as a result of which the phenomenon of softening of toner due to heat produced by friction as a result of contact between sealing materials and low-melting-point toners as well as problems occurring in accompaniment thereto have become more prominent. For this reason, as prior art, a sealing material has been proposed which is a sealing material comprising woven pile fabric, and which is such that at least a portion of the pile yarn that makes up the pile is formed in such fashion as include a material having heat-dissipating functionality (e.g., see Patent Reference No. 4). However, this sealing material cannot be said to be a sealing material that is adequate in terms of ability to accommodate increased speed and decreased particle diameter of toner.